Mixed tumor of the parotid gland (or pleomorphic adenoma) is a common benign tumor of the parotid gland. It presents as a solid mass of moderate firmness in the parotid area (under or in front of the ear) with a nodular (or smooth) surface, clear borders, mobility, no pressure pain, slow growth, and no obvious conscious symptoms. Surgery is currently the only effective treatment for mixed tumors of the parotid gland. Although parotid gland mixed tumor is benign, it can also become cancerous. If the tumor has one of the following conditions, it should be considered as possibly cancerous or in the process of cancerous transformation, and it is recommended to receive regular surgical treatment as soon as possible: 1. The recent growth of the tumor suddenly accelerates, and the tumor body (mass) increases significantly. 2. 2.The mobility of the tumor (mass) is reduced, or even fixed and cannot be pushed. 3.Tumor and local skin show symptoms of abnormal sensation such as scratching, insect crawling sensation or pain. 4.Facial paralysis occurs on the same side. 5. Due to incomplete envelope, parotid mixed tumor is prone to recurrence after surgery, and the incidence of cancer increases greatly in patients with multiple recurrences.